Describe the role of UNCLOS and the key maritime zones it defines.

• A. A regional treaty governing land borders.
• B. A framework for coastal city development.
• C. An agreement that defines maritime zones and rights under international law.
• D. The United Nations Convention on the Law of the Sea; defines Territorial Sea (0–12 nautical miles), Contiguous Zone (12–24 nm), Exclusive Economic Zone (up to 200 nm), and the continental shelf rights.

Answer: (D)

UNCLOS, the United Nations Convention on the Law of the Sea, is the binding international framework that governs how oceans and their resources are used and by whom. It lays out a system of maritime zones and the rights and responsibilities that come with each, helping states manage navigation, resource use, and environmental protection while reducing conflicts at sea.

In the closest zone, a coastal state has full sovereignty over the waters up to 12 nautical miles from its baseline, though innocent passage by vessels of all states is allowed. Beyond that, up to 24 nautical miles, is the Contiguous Zone, where the state can enforce laws related to customs, immigration, sanitation, and fiscal matters to prevent infringement of its laws within the territorial sea. Further out is the Exclusive Economic Zone, extending to 200 nautical miles, where the coastal state has exclusive rights to explore and exploit natural resources in the water column, on the seabed, and in the subsoil, while other states retain freedom of navigation and overflight and the laying of cables and pipelines. The continental shelf refers to the seabed and subsoil of the shelf beyond the territorial sea; the coastal state has rights to exploring and exploiting resources on and under the shelf, potentially beyond 200 nautical miles if geological criteria allow, under specific UNCLOS rules.

This framework clarifies who controls what at sea and why, rather than addressing land borders or city planning.